Cutting edge for excavating devices

ABSTRACT

AN EXCAVATING DEVICE SCOOP WHEREIN THE LIP IS EQUIPPED WITH FORWARDLY EXTENDING EXCAVATING TEETH WHICH ADDITIONALLY SERVE TO CONFINE WEAR SHROUNDS.

Nov. 23, 1am F HAHN ETAL $621,594

CUTTING EDGE FOR EXCAVATING DEVICE Filed Feb. 13. 1969 4 Sheets-Sheet lNov. 23, 1971 HAHN ETAL 3,621,594

CUTTING EDGE FOR EXCAVATING DEVICE Filed Feb. 13, 1969 4 Sheets-Sheet 223, 1971 F. c. HAHN ETAL 62L594 CUTTING EDGE FOR EXCAVATING DEVICE FiledFeb. 13. 1969 4 Sheets-Sheet 5 INVHNTURS m ma Km Ewe/(Z26 m 5 59 54a 34/a m, Maw/0g NOV. 23, 1971 HAHN ETAL $621,594

CUTTING EDGE FOR EXCAVATING DEVICE Filed Feb. 13, 1969 4 Shoots-Shoot AUnited States Patent O US. Cl. 37-141 2 Claims W I a um ABSTRACT OF THEDISCLOS BACKGROUND OF THE INVENTION This invention relates to excavatingdevices used in earth moving, earth working, and the like. The termscoop is used in its generic sense herein and relates to such variedelements as front end loaders (used illustratively herein) buckets,dippers, etc. Such elements can be used to scrape or penetrate theground and, if desired, relocate the earth to another site. As such,these scoops are provided with forwardly facing lips (as in thedirection of element movement during normal ground engagement), and thisterm again is used in its generic sense referring to both horizontallyelongated and generally vertically elongated edges, whether they be onthe floor or bottom of the scoop or on sides or wings thereof. Stillfurther, the scoops are equipped with forwardly projecting tooth membersto facilitate penetrating the earth and this term also is usedgenerically, referring (as illustrated) to such forms as two piece teethwherein adapters are releasably connected to the scoop and in turnsupport removably mounted points. Other tooth members may include suchknown structures as single piece teeth wherein a wedge-shaped point hasa rearwardly facing socket mounted on a nose which projects forwardlyfrom and integrally with the scoop lip.

The prior art has :made use of shroud both for the bottom wall lip inbetween the forwardly projecting tooth members and also along the lipsof the wings. In most cases, these shrouds or wear pieces have beenwelded to the associated lips. In other cases, there was no provisionfor wear protection and replacement when the lip was worn out. In stillother cases, the lips were hard faced, requiring extensive work forreplacement. None of the above procedures minimized a lip maintenance.All required the use of burning or welding to maintain the lips in acondition whereby the given piece of earth mov ing equipment could beoperated. With larger units it was frequently necessary for the user toown several units for one machine so that they could be rotated from useon the machine to the maintenance shop.

SUMMARY OF THE INVENTION The inventive concept for minimizing lipmaintenance includes the following aspects: 1) all areas of the lip andadjoining parts which normally encounter high rates of wear due tocontact with the material being moved or excavated are protected by wearand cutting edges. The only wear which occurs on the lip and adjoiningparts is that associated with contact with the wear and cutting edges,and this is kept to a minimum through close fit of the edges to the lipin order to prevent movement of the edges over the lip; (2) the lips areespecially adapted for use of wear and cutting edges. Unlike presentpractice where lips are constructed with some built-in wear material towhich may be added additional wear metal through the use of shrouds,these lips usually contain no 3,621,594 Patented Nov. 23, 11971 iceextra wear metal; (3) the edges are mechanically held in place byquick-change locking devices requiring only seconds for engagement ordisengagement; and (4) wear edges and cutting edges are of a segmentedconstruction, i.e., small edge segments of the overall whole arereplaceable without the necessity of removing all or large portions ofthis whole.

DESCRIPTION OF THE DRAWING The invention is described in conjunctionwith the accompanying drawing, in which- FIG. 1 is a perspective view ofa six-yard front end loader bucket constructed and equipped according tothe teachings of this invention;

FIG. 2 is a schematic sectional view of the bucket of FIG. 1 featuringthe cut-back wings;

FIGS. 3-5 are fragmentary perspective views of the left-hand corner ofthe bucket of FIG. 1 with certain of the replaceable elements beingshown in different stages of installation;

FIG. 6 is a longitudinal, i.e. fore-and-aft sectional view on enlargedscale such as would be seen along the sight line 66 of FIG. 5;

FIG. 7 is a fragmentary sectional view taken along the line 7-7 of FIG.6;

FIG. 8 is a fragmentary sectional view of a modified form of theinvention and corresponds essentially to the showing in FIG. 7;

FIG. 9 is a longitudinal sectional view of a modified form of theinevntion and corresponds essentially to the showing in FIG. 6;

FIG. 10 is a transverse sectional view taken along the line 1010 of FIG.9;

FIG. 11 is a fragmentary top plan view of the scoop of FIG. 9';

FIG. 12 is a fragmentary perspective view of the loader of FIG. 1 butseen from the rear right, and showing the corner adapters and wingshrouds;

FIGS. 13 and 14 are fragmentary perspective views of corner adapters;

FIG. 15 is a fragmentary top plan view of a modified form of scoop;

FIG. 16 is a fragmentary perspective view of the embodiment of FIGS.9-11; and

FIG. 17 is an exploded fragmentary perspective view of the embodiment ofFIGS. 9-11.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1, thenumeral 30 designates generally a front end loader bucket or scoop. Asindicated previously, the invention is useful in conjunction withvarious lip-equipped devices such as shovel clippers, drag lines, wheellips, hoe dippers, front end loaders and the like. In FIG. 1, it is seenthat a scoop center 31 and right-hand and left-hand wings 32 and 33,respectively, are Welded together into the scoop 30 as the basic scoopstructural member. The bucket 30 adjacent its forward lower end isequipped with a lip generally designated 34 (better seen in FIG. 3).This lip 34 is provided with hearing pads as at 35 and slots as at 36for the various attachments and locking devices. The wings as at 33 inFIG. 2 are cut back as at 33a relative to the dashed line 30' which isthe usual forward edge of the wings.

In FIG. 3, it will be seen that a workman 37 is in the process ofinstalling a shroud 38 on the lip 34. The shroud may have a variety ofcross-sectional configurations, i.e., V-shaped, U-shaped, L-shaped,etc., as can be appreciated from a consideration of FIGS. 6 and 9.

Once the shroud 38 is positioned as seen in FIGS. 3-5 an adapter 39 isinstalled in position by the workman 37 in the fashion seen in FIG. 4.The adapter 39 is seen to have rearwardly extending legs 40 and 41 withthese legs being apertured as at 42 for the receipt of a locking meansgenerally designated 43. In the illustration given, the locking means 43includes a fluted wedge and spool as can be appreciated from acomparison of FIGS. and 6. Alternatively, a C-clamp can be employed. Atits forward end, the adapter 39 is equipped with a generallywedge-shaped nose portion 44 (see (FIG. 6) on which is installed asocket-equipped point 45. The nose 44 and point 45 are held together bymeans of a locking key mechanism des ignated 46 (see FIG. 5).

In the illustration given in FIG. 4, the side walls of the adapter 39are recessed as at 47 so as to conform to the outer contour of theadjacent shrouds 38 and confine the same in place. Thus, it isunnecessary to provide any welding or lock means to positively connectthe shroud 38 to the lip 34.

From the foregoing, it will be noted that the shrouds or wear pieces 38are actually part of the basic lip cross section and thereby eliminatedextra weight, loading obstructions, and digging efficiency losses. Also,because the wear-resistant elements are added to a basic lip, the usercan retailor his scoop to include different styles of teeth or areplaceable leading edge without any teeth but with the shrouds held byholders to make the scoop a more universal tool. The lip shroud 38 iseffectively extended by plate shrouds as at 48 in FIGS. 6 and 7 whichalso fit into the recesses 47. (The plate shrouds being omitted from theshowings in FIGS. 3-5 for clearness of pieturization.) These platesoverlie the bottom wall 31a of the scoop, somewhat rearward of the lip34.

In addition to the method of securement seen in FIGS. 1-7, the formillustrated in FIG. 8 is useful. In FIG. 8, the bottom wall of thecenter 31, scoop 30 is also designated by the reference numeral 31a andthis is somewhat rearward of the lip 34 and over the slight bearing pads35. The area 25 is subjected to extreme wear in use. As an alternativeto the plate shroud 48, we employ an augmented shroud designated 148. Itis seen that there is a dissimilar material 149 sandwiched between thebottom wall 31a and the shroud 148, this being designated 149. Forexample, this can take the form of a resilient flexible material such asrubber for improving shock resistance. Alternatively, the wall 31a andthe shroud 48 or 148 may be spaced apart with asbestos in place of therubber to provide a thermal barrier for high temperature operation. Incertain cases, an air gap may be introduced between the inside surfacesof the lip and plate shrouds and the lip properthis serving toeffectively increase the gradient between the ambient temperature andthe basic structural lip temperature. Exemplary of high temperatureoperation is moving hot slag where front end loaders mounted on crawlertype machines have been found to be the most economical and best suitedto handling slag in the 700 to 1100 F. range. The high ambienttemperatures created, however, tended to take the temper out of thesteel in the bucket and reduce its service life accordingly. Through themodification just described, this drawback has been eliminated.

In the practice of the invention, generally, it is seen that there isprovided a rearwardly facing bearing surface on the tooth member whichcooperates with a forwardly facing bearing surface on the shroud. Thesesurfaces, if not already in bearing engagement will quickly movethereinto when a force tending to dislodge the shroud is applied tothem. Normally, however, the parts are structured so that this bearingengagement does exist and therefore the shroud is removably locked inplace on the scoop by the tooth member and without the need of weldingor the like. In the illustration given in FIGS. 1-8, this lockingengagement is achieved through the provision of the recess 47 on theside of the adapter. Because of the grooves or recesses 47 extending theentire length of the adapter, wear plates are readily installed (andequally readily removable) to completely armor the inside top face ofthe lip from the ravages of wear. l e

In the modification seen in FIGS. 9 through 11, the tooth member isstructured somewhat differently in that a nose-providing element 239 isprovided integral with and projecting forwardly from the scoop bottomwall 31a as if the adapter 39 of FIG. 4 were cast integrally with thescoop. The nose portion of the element 239 is designated again by thenumeral 44 and this receives a wear point 45. The wear point 45 isequipped with a wedge-shaped socket 45a extending forwardly into thepoint from the rear thereof. The socket-defining walls terminate at therear as at 4512 and these walls laterally overlap the forward endsurfaces 238a of the shroud 238 to again confine the same in place in afashion analogous to that seen in FIGS. 1-8. In the FIGS. 9-11 showinghowever, the shroud 238 is held on by a butt fit between the extremesides of the shroud and the back edge 45b of the tooth point 45. Theshroud 238 in FIG. 11 has an arcuate leading edge giving the bucket ascalloped appearancethe'extreme sides 238a being further forward thanthe center part 238b, as seen in FIG. 11. No mechanical locking devicesother than the standard locking device 46 is utilized.

In the sectional view seen in FIG. 10, a dovetail or enlarged edge isseen as at 238a to facilitate holding the shroud 238 in place. Acorresponding arrangement can be utilized relative to the center shroudsas seen in FIG. 9. There the shroud 238 is seen to be equipped with arearwardly-extending tongue 250 and the scoop bottom wall recessedcorrespondingly as at 251.

Through the practice of the invention, a number of advantages accrue,particularly obtaining longer and more effective Working life withoutincreasing the thickness of the front top surface of the lip whichordinarily would add weight, create additional obstructions for thematerial to load over, and shortening the effective digging andpenetrating distance of the tooth member tip from.

the leading edge of the scoop.

More specifically, the inventive arrangement allows the elimination of alarge part of the normally required welding maintenanceutilizingmechanical connections in stead. Also, the segmented construction of theedges results in individual pieces small enough to make it feasible todiscard them when worn out rather than to rebuild them through theexpensive and laborious process of welding. It is now practical tomaintain a more efficient digging configuration because the low cost interms of time and labor for installation makes it reasonable to useedges with less wear metal and a correspondingly sharper configurationthan was previously considered reasonable. Also, the lack of extra wearmetal on the lip itself makes it possible to further enhance diggingconfiguration. Im-

proved output of the scoop then results from its superior Referring nowto FIG. 12, a corner adapter generally designated 52 is seen. Theadapter 52 has three legs. One leg 53 is clearly seen in FIG. 12. Asecond leg 54 is seen in FIG. 3 and is on the inboard side of the wing33. The

third leg 55 is the bottom leg. Thus, the legs of the adapter" 52 flankthe bottom wall of the scoop as well as each wing. The adapter 52 isremovably fixed to the wing 32 (as in FIG. 10) by means of a lockingdevice 56. The wing shroud 57 is seen to overlie the wing lip (masked inFIG. 12) but again is held in place by means of coacting bearingsurfaces in the area designated 58 in FIG. 12,"

Le, a rearwardly facing bearing surface on the tang 59 of the wingshroud 57 and a forwardly facing bearing surface on the tang 60 of thelip 32. The forward or lower portion of the wing shroud 57 is equippedwith a knoblike projection or tang 61 (seen only in FIG. 13). This mateswith a corresponding recess or groove in the rearward or upwardly facingsurface of the corner adapter 52. Additionally, FIG. 13 shows aprotrusion 62 extending forwardly from the lip 34 which mates with acorresponding recess in the adapter 52. A similar projection 63 can beseen in FIG. 3 for the purpose of accommodating the mounting of thecenter adapters 39. It will be noted in FIG. 12 that the corner adapter52 is recessed as at 64 in the same fashion as the center adapters 39.Recesses 55 are provided on both sides of each corner adapter 52 butonly one is used.

In the embodiment of FIGS. 1 and 12, it is possible also to have theoutboard mounting of the corner tooth as illustrated by the mounting ofthe point 45 in FIG. 12. According to the invention, the corner teethare mounted in an extreme outboard configuration thereby cuttingclearance from the sides, reducing wear, and at the same time improvingthe penetrating and breakout efliciency of the corner lip area. As thecorner tooth is located closer to the center of the lip (as inconventional designs), it has less capability of directing the materialas it breaks up into the bucket or outside the bucket in the event it isdirected in that manner due to its shape. For example, a rock which mayhave the tendency to go either inside or outside of the bucket is nowproperly guided by the extreme comer-mounted tooth without markedlyslowing the loading action. If a rock or group of rocks are allowed toball up in the lip wing area, this slows down the loading action andactually retards the ability of the bucket to get a full load. Inessence, we attempt to at least have the longitudinal center line of thetooth on the longitudinal center line of the wing-the tooth having asignificantly greater width than the wing whereby a substantial outboardmounting is achieved.

The invention also has the advantage of the cut-back sides or wings onthe bucket which is made possible by shrouds on the lip wing. Theshrouds have the high strength-to-weight ratio available in castproducts. As can be seen in FIG. 2, there is a substantial recessing ofthe wings relative to that normally designed into buckets and thispermits more horizontal movement into the material to be excavated andenhances the ability of the bucket to penetrate-tending to improve theamount of material that is loaded on the average in each pass.

FIG. shows a modification made available through the practice of theinvention. As mentioned previously, we can retailor the front edge ofthe lift to different configurations. For example, in FIG. 15, thestraightacross type of shroud employed in the FIG. 1 arrangement hasbeen replaced with shrouds as at 338-342 which build the lip into a Vconfiguration.

We claim:

1. An excavating scoop having a forwardly projecting lip, a plurality ofspaced-apart excavating teeth releasably mounted on said scoop andprojecting forwardly of said lip, and a plurality of shrouds mounted onsaid scoop between said teeth and extending around said lip to protectthe same, each of said teeth having a portion overlapping an adjacentshroud, said overlapping portions constituting the sole means to holdsaid shrouds in place, said lip being flanked by upwardly extending sidewalls terminating in a generally upwardly and forwardly facing wingedge, a wing shroud on each wing edge, an adapter mounted on said scoopstraddling said lip and engaging said wing shroud, and a projection andrecess interconnecting each wing shroud with each of said wing edge andthe adapter associated therewith and arranged so that said adapter mustbe removed before removing said wing shroud.

2. The structure of claim 11 in which said adapter includes a unitarybody having a forwardly facing nose and three rearwardly extending legs,two of said legs being positioned above a third of said legs, said twolegs being spaced from said third leg to straddle said lip, said twolegs being spaced from each other to straddle one of said side walls,aligned openings in said two legs for the receipt of means for securingsaid adapter to said one side wall.

References Cited UNITED STATES PATENTS 1,796,737 3/1931 Van Buskirk37-142 1,803,654 5/1931 Ronk 37-141 X 1,843,205 2/1932 Clark 37-1411,920,873 8/ 1933 MacFadyen 37-141 3,001,591 9/1961 Johnson 37-142 X1,340,385 5/1920 Edmondson 37-142 1,815,649 7/1931 Edmunds 37-1422,229,267 1/ 1941 Younie 37-142 2,991,569 7/1961 Launder 37-142 R3,281,972 11/1966 Kerestes 37-141 3,388,488 6/1968 Duplessis 37-1423,456,370 7/1969 Gilbertson 37-141 3,462,861 8/1969 Kampert 37-1423,465,833 9/1969 Lutz 37-141 X 3,478,449 11/1969 Baker 37-141 3,497,9733/1970 Campbell 37-141 FOREIGN PATENTS 490,651 1953 Canada 37-142988,844 1965 Great Britain 37-118 EDGAR S. BURR, Primary Examiner US,Cl. X3. 37 142

